The Kirk itself is well worth a look in, whether you’re religious or not. As you stand above the basin and footprint (sorry the photo’s pretty poor) there are some steps leading down into the Den, and on the left as you go is a well-defined carving of Celtic knotwork. Round the small promontory bearing the large cross is a small Celtic Trinity, about 9” diameter. Very dark under the trees the day I was there, so the photo’s been enhanced a bit and isn’t very clear. Well worth a visit though.